My physics teacher assigned us an extra credit project for Halloween where we had to launch mini pumpkins with an original, hand-made catapult and hit the target on the other side of a 2-meter high bar. The number of points we got depended on how close we were to the bullseye. Around a third of the class participated; most people avoided it because of the time and energy needed to make a catapult. I was always interested in physics and engineering, so I couldn’t not try.

I started with looking through the many catapult designs online and decided on a Wyvern Catapult—I was so sure it would get me those extra credit points. I went to Home Depot and got the right types and amounts of wood needed, as well as a 40-ft rope and some nails & screws. After getting home, my parents cleared out the garage for me and I immediately went to work.

I used a saw to cut a piece of wood diagonally to create two triangles for supporting the sides—30 minutes. I nailed the triangle to the base of the catapult, and worked on building the base. I couldn’t contain the frustration I had for myself for working so slow and inefficiently—time went by so fast. I had to drive back to Home Depot to get longer screws (thank you mom <3). It went pretty well. I was able to get to the part where I tied the ropes to provide the spring mechanics and by the time I finished after 7 hours of work, it was around 10pm. I have to go test it.


This was taken outside my house around 11pm after numerous renovations. At this point, I was trying out anything I can to increase the power and have the pumpkin fly farther.

It was already late, so I grabbed handful of the cotton spider webs from the Halloween decorations on my house and stuffed it between the arms and the catapult to test out the catapult as quiet as I can. I dragged the heavy thing outside my house and measured 10 meters from the start line—the distance to the bullseye. I pulled back the arm. Then I released the pumpkin.

It went no more than 3 meters in length and 1 meter in height. There was no way that it could go over the 2-meter bar or reach the 10-meter bullseye.


I thought maybe the problem was in the way I tied the rope, so I took it off and tried tying it much tighter this time in hopes of increasing the spring mechanic. The cardboard rolls broke. I got a brand new toilet plunger from my house and broke it in half (sorry mom) to replace the broken cardboard rolls. It went about 5 meters—little improvement!

Then, I went back inside the garage and put on an unused tennis racket on the arm to see if that would help the pumpkin fly higher. It didn’t (It actually made the arm heavier and slowed down the speed). At this point, there was no plan; I was doing everything I can to just make the pumpkin go farther.

Bungee cord! Could a bungee cord add more tension on the arm, allowing the catapult to throw the pumpkin farther? Yes it did!! I tested it out—it worked. Now I could only hope for the catapult to not break down before the big day. It took me over 12 hours total, excluding the shopping for wood, etc.

We were able to get 12 extra credit points, which was not so bad. I was proud of myself for putting together something that I had never done before.

We can’t be afraid of renovating. It’s rather hard to admit the things we don’t know. It goes against our pride when we say, “I don’t know the answer. What can I do to improve it?” We have to realize, there are no limits to how many times we can try. I just read a Japanese book today called Becoming a True Elite, and a phrase hit me.

Intellectual honesty.

We need to start opening our eyes to our “blind spots” and find passion in true learning—not the kind of learning where we memorize the textbook the night before tests.

What a fool I’ve been.


Success~ The yellow bungee cord and the pumpkin that I had to borrow from another group because all my pumpkins were destroyed from the previous nights.


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